Object.defineProperties(Array.prototype, {
    count: {
        value: function (query) {
            /* 
               Counts number of occurrences of query in array, an integer >= 0 
               Uses the javascript == notion of equality.
            */
            var count = 0;
            for (let i = 0; i < this.length; i++)
                if (this[i] == query)
                    count++;
            return count;
        }
    }
});

const mean = arr => arr.reduce((p, c) => p + c, 0) / arr.length;

tables = $(".table-div");


function generateExtra() {
    $(".auto-generated").remove();
    global_shifts = new Set();

    total_summed_shift_diffs = 0;
    total_summed_shift_diffs_abs = 0;

    tables.each((n, table) => {

        rows = $(table).find(".worker-row");

        workers = {};

        rows.each((n, tr) => {


            worker_td = $(tr).find("td:first");

            worker = worker_td.attr("data-worker");

            shift_tds = $(tr).find(".rota-day");
            shifts = []

            shift_tds.each((n, td) => {
                shifts.push($(td).attr("data-shift"));
            })

            shifts_unique = new Set(shifts);
            shifts_unique.delete("");
            global_shifts = new Set([...global_shifts, ...shifts_unique]);

            weekends_worked = 0;

            weeks = shift_tds.length / 7;

            whole_weekends_worked = 0;

            for (var i = 1; i <= weeks; i++) {
                if ($(tr).find(`[data-week='${i}'][data-day='Sat']`).attr("data-shift") != "" || $(tr).find(`[data-week='${i}'][data-day='Sun']`).attr("data-shift") != "") {
                    weekends_worked = weekends_worked + 1;
                }
                if ($(tr).find(`[data-week='${i}'][data-day='Sat']`).attr("data-shift") != "" && $(tr).find(`[data-week='${i}'][data-day='Sun']`).attr("data-shift") != "") {
                    whole_weekends_worked = whole_weekends_worked + 1;
                }
            }

            shift_counts = {};

            total_shifts = 0;
            days_lost = 0;
            shifts_unique.forEach(el => {
                shift_counts[el] = shifts.count(el);
                total_shifts = total_shifts + shifts.count(el);

                // why like this?
                if (el == "night_weekend") {
                    whole_weekends_worked = whole_weekends_worked - shifts.count(el) / 3
                }

                if ($("#global-settings").length == 1) {

                    n = $(`#${el}-tdl`).val();
                    if (!isNaN(n)) {
                        days_lost = days_lost + shifts.count(el) * n;
                    }


                }

                // // 5 days for weekday nights
                // if(el == "night_weekday") { days_lost = days_lost + shifts.count(el) / 4 * 5 }
                // // 4 days for weekend nights
                // if(el == "night_weekend") {
                //     days_lost = days_lost + shifts.count(el) / 3 * 4
                //     //whole_weekends_worked = whole_weekends_worked - shifts.count(el) / 3
                // }
                // // 0.5 for twilights
                // if(el.includes("twilight")) {
                //     twilight_days_lost = shifts.count(el) / 2
                //     days_lost = days_lost + twilight_days_lost

                // }

            });

            // Also 1 day for a whole weekend
            days_lost = days_lost + whole_weekends_worked

            // Highlight non working days
            nwds = JSON.parse(worker_td.attr("data-nwds"));
            nwds.forEach(element => {
                // Restrict to date ranges
                start_date = new Date(Date.parse(element[1]))
                end_date = new Date(Date.parse(element[2]))
                $(shift_tds).filter(`.${element[0]}`).each(
                    (n, td_el) => {
                        td_date = new Date(Date.parse(td_el.dataset.date));

                        if (td_date >= start_date && td_date < end_date) {
                            $(td_el).addClass("nwd");
                        }

                    }

                )
            });

            workers[worker] = {
                "site": worker_td.attr("data-site"),
                "nwds": worker_td.attr("data-nwds"),
                "fte": worker_td.attr("data-fte_adj"),
                "end_date": worker_td.attr("data-end_date"),
                "shift_diff": worker_td.attr("data-shift-diff"),
                "shifts": shifts,
                "shift_types": shifts_unique,
                "weekends_worked": weekends_worked,
                "shift_counts": shift_counts,
                "days_lost": days_lost,
                //"shifts"
            }

            sc = JSON.stringify(shift_counts);


            bank_holidays = shift_tds.filter(".bank-holiday").filter(function (i) {
                return $(this).attr('data-shift') != "";
            });

            bank_holidays_worked = bank_holidays.length;

            shift_diff = JSON.parse(worker_td.attr("data-shift-diff"));
            summed_shift_diff = Object.values(shift_diff).reduce((a, b) => a + b);

            total_summed_shift_diffs = total_summed_shift_diffs + summed_shift_diff;
            total_summed_shift_diffs_abs = total_summed_shift_diffs_abs + Math.abs(summed_shift_diff);

            worker_td.get(0).dataset.shiftDiffSummed = summed_shift_diff.toPrecision(2);


            worker_td.after(`<div class='worker-summary auto-generated'>
            <span>Total shifts: ${total_shifts}, </span>
            <span>Weekends: ${weekends_worked}, </span>
            <span>Bank holidays: ${bank_holidays_worked}, </span>
            <span class='shift-diff-span'>Summed shift diff: ${summed_shift_diff.toPrecision(2)}, </span>
            
            </div>`)

            if (summed_shift_diff >= 1) {
                worker_td.addClass("large-shift-diff-pos")
                $(tr).find(".shift-diff-span").addClass("large-shift-diff-pos")
            } else if (summed_shift_diff <= -1) {
                worker_td.addClass("large-shift-diff-neg")
                $(tr).find(".shift-diff-span").addClass("large-shift-diff-neg")

            }

        })


        sites = {};
        sites_days_lost = {}
        for (const worker in workers) {
            w = workers[worker];
            if (w.fte == 100) {
                for (let shift of w.shift_types) {
                    if (!(w.site in sites)) {
                        sites[w.site] = {};

                    }
                    if (!(shift in sites[w.site])) {
                        sites[w.site][shift] = [w.shift_counts[shift]];
                    } else {
                        sites[w.site][shift].push(w.shift_counts[shift]);
                    }
                }
                if (!(w.site in sites_days_lost)) {
                    sites_days_lost[w.site] = [w.days_lost];

                } else {
                    sites_days_lost[w.site].push(w.days_lost);
                }
            }
        }

        // Calculate site shift summaries
        // $(table).append("<div class='site-summary auto-generated'>Average shifts for a 100% FTE trainee</div>");

        // for(const site in sites) {
        //     $(table).find(".site-summary").append(`<div class='site site-${site}'><span class='site-name'>${site}</span></div>`);

        //     for(const shift in sites[site]) {
        //         average = mean(sites[site][shift])
        //         $(table).find(`.site-${site}`).append(`<div>${shift}: ${average.toFixed(2)}</div>`);
        //     }

        //     days_lost_avg = mean(sites_days_lost[site]);
        //     $(table).find(`.site-${site}`).append(`<div class='training-days-lost'>Training days lost: ${days_lost_avg.toFixed(2)}</div>`);
        // }

        summary_button = $("<button class='auto-generated'>Toggle Summary</button>").click(() => {
            $(table).find(".rota-day").toggleClass("hidden");
            $(table).find(".worker-summary").toggle();

        });


        $(table).before($(`<span>Total summed shift diff: ${total_summed_shift_diffs}</span><br/>`));
        $(table).before($(`<span>Total summed shift diff: ${total_summed_shift_diffs_abs}</span><br/>`));
        $(table).before(summary_button);



    });
    return global_shifts
}

shifts = generateExtra();

if (shifts.size < 1) {
    shifts = $("#shifts-container").data("shifts");
}

oshifts = Array.from(shifts).sort()

$("body").append("<div><button id='show-colour-diff'>Show colour diff</button><table class='tsummary'></table></div>")
$("#show-colour-diff").on("click", (evt) => {
    $("table.tsummary").find(`td.target-assigned`).toggleClass("no-colour");
});

$("table.tsummary").append("<tr class='header'></tr>");
h = $("table.tsummary tr.header");
h.append(`<th>Worker</th>`);
h.append(`<th>Site</th>`);
h.append(`<th>FTE</th>`);
h.append(`<th>FTE (adj)</th>`);


oshifts.forEach((s) => {
    h.append(`<th>${s}</th>`);

});



$(".table-div .worker-row .worker").each((n, tr) => {
    //worker_td = $(tr).find("td").first();
    jtr = $(tr);
    row = $("<tr></tr>");
    row.append(`<td>${jtr.data("worker")}</td>`)
    row.append(`<td>${jtr.data("site")}</td>`)
    row.append(`<td>${jtr.data("fte")}</td>`)
    row.append(`<td>${parseFloat(jtr.data("fte_adj")).toFixed(2)}</td>`)

    if (jtr.data("shift-diff-summed") >= 1) {
        row.addClass("large-shift-diff-pos")
    } else if (jtr.data("shift-diff-summed") <= -1) {
        row.addClass("large-shift-diff-neg")

    }

    shift_counts = jtr.data("shift-counts")
    shift_targets = jtr.data("worker-targets")

    oshifts.forEach((s) => {
        if (s in shift_targets && shift_targets[s] > 0) {
            if (s in shift_counts) {
                c = shift_counts[s];
            } else {
                c = 0;
            }
            row.append(`<td class="target-assigned ${s}" data-assigned=${c} data-target=${shift_targets[s].toFixed(2)} data-diff=${shift_targets[s].toFixed(2)-c}>${c} (${shift_targets[s].toFixed(2)})</td>`)

        } else {
            row.append(`<td>-</td>`)
        }
    })

    $("table.tsummary").append(row)
})

shift_max_diff_map = {};
shift_min_diff_map = {};

oshifts.forEach((s) => {
    shift_max_diff_map[s] = 0;
    shift_min_diff_map[s] = 0;
    $("table.tsummary").find(`td.target-assigned.${s}`).each((n, td) => {
        shift_max_diff_map[s] = Math.max(shift_max_diff_map[s], td.dataset.diff)
        shift_min_diff_map[s] = Math.min(shift_min_diff_map[s], td.dataset.diff)
    })

});

oshifts.forEach((shift) => {
    $("table.tsummary").find(`td.target-assigned.${shift}`).each((n, td) => {
        diff = td.dataset.diff;

        if (diff > 0) {
            max_diff = shift_max_diff_map[shift];
            var h = 120 - Math.floor((max_diff - diff) * 120 / max_diff);
            var s = diff / max_diff;
            //var s = 0.5;
            var v = 1;
            $(td).css({
                backgroundColor: hsv2rgb(h, s, 1)
            })
        } else {
            min_diff = shift_min_diff_map[shift]

            var h = Math.floor((min_diff - diff) * 120 / min_diff);
            var s = diff / min_diff;
            //var s = 0.5;
            var v = 1;
            $(td).css({
                backgroundColor: hsv2rgb(h, s, 1)
            })

        }
        $(td).addClass("no-colour")
        //s = Math.max(shift_max_diff_map[s], td.dataset.diff)
        //shift_min_diff_map[s] = Math.min(shift_max_diff_map[s], td.dataset.diff)
    })

});

oshifts.forEach((shift) => {
    button = $(`<button data-shift='${shift}'>${shift}</button>`)

    button.on("click", (evt) => {
        console.log(evt.target.dataset.shift)
        $("#shift-timetable-div").empty();
        table = $("<table>");
        $("table#main-table th.date").each((n, th) => {
            row = $("<tr>")
            row.append(`<td>${th.dataset.date}</td>`);
            $(`table#main-table td[data-date='${th.dataset.date}'][data-shift='${evt.target.dataset.shift}']`).each((n, td) => {

                //row.append(`<td>${}</td>`)
                row.append($(td).closest("tr").children("td:first").clone())

            });

            table.append(row)
        });
        $("#shift-timetable-div").append(table);

    })

    $("#shift-timetable-options").append(button)
});

//$("table.summary")

// $("body").prepend("<div id='global-settings'>Settings:<br />Customise training days lost per shift (you need to press recalculate for changes to take effect)<form></form></div>")

// shifts.forEach((s) => {

//     disable = false;
//     if(s.includes("twilight")) {
//         value = 0.5;
//     } else if(s == "night_weekend") {
//         value = 4 / 3;
//     } else if(s == "night_weekday") {
//         value = 5 / 4;
//     } else {
//         disable = true;
//         value = 0;
//     }

//     if(!disable) {
//         $("#global-settings form").append(`<span class='tdl-settings'><label for="${s}-tdl">${s}</label><input type="number" id="${s}-tdl" name="${s}-tdl" value='${value}'></span>`);
//     }


// })
// $("#global-settings").append($("<button >Recalculate</button>").click(() => {
//     generateExtra();
// }))

// generateExtra();

$(".table-div + pre").each((n, pre) => {

    $(pre).before($("<button class='shift-breakdown-button'>Show shift breakdown</button>").click(() => {
        $(pre).toggle();
    }));

})

$("td").hover((e) => {
    //start hover
    worker_td = $(e.target).closest('tr').find('td:first')[0]
    pair = worker_td.dataset.pair;
    index = $(e.target).index() - 1;
    if (pair > 0) {
        $(`td[data-pair=${pair}]`).each((n, el) => {
            $($(el).closest('tr').find('td').get(index)).addClass("pair-match")
        })
    }
    if (e.target.dataset.shift != undefined && e.target.dataset.shift.length > 0) {
        $(`td[data-shift=${e.target.dataset.shift}]`).addClass("shift-highlight")


        $(`td[data-remote-site='${e.target.dataset.shiftRemoteSite}']`).closest('tr').find(`td[data-shift=${e.target.dataset.shift}]`).addClass("remote-site-match")
        // if (e.target.dataset.shiftRemoteSite == worker_td.dataset.remoteSite) {
        //     $(`td[data-shift-remote-site=${e.target.dataset.shiftRemoteSite}]`).addClass("remote-site-match")
        // }
    }

}, (e) => {

    //end hover
    $("td.pair-match").removeClass("pair-match")
    $("td.shift-highlight").removeClass("shift-highlight")
    $("td.remote-site-match").removeClass("remote-site-match")

})

$("#rota-table tr td:first-child").each((n, td) => {
    $(td).click(() => {
        viewWorker(td);
    })
})

function viewWorker(worker) {
    ds = worker.dataset;
    let exactShiftsText = "(none)";
    if (ds.exactShifts) {
        try {
            let parsed = JSON.parse(ds.exactShifts);
            if (Object.keys(parsed).length > 0) {
                exactShiftsText = Object.entries(parsed).map(([s, c]) => `${s}: ${c}`).join(", ");
            }
        } catch(e) {}
    }
    dlg = $(`<div class='dialog' title='${ds.worker}'>
    Site: ${ds.site}</br>
    FTE: ${ds.fte} (${ds.fte_adj})</br>
    Exact shifts: ${exactShiftsText}</br>
    Start date: ${ds.start_date}</br>
    End date: ${ds.end_date}</br>
    Non working days: ${ds.nwds}</br>
    Remote site: ${ds.remoteSite}</br>
    Summed shift diff: ${ds.shiftDiffSummed}
    </div>`)
    $("body").append(dlg)

    shifts = JSON.parse(ds.shiftCounts)
    shift_targets = JSON.parse(ds.workerTargets)
    shift_diffs = JSON.parse(ds.shiftDiff)

    let shift_count_table = document.createElement("table")
    shift_count_table.classList.add("shift-table")
    let header_row = shift_count_table.createTHead().insertRow();
    header_row.insertCell().appendChild(document.createTextNode("Shift"))
    header_row.insertCell().appendChild(document.createTextNode("Count"))
    header_row.insertCell().appendChild(document.createTextNode("Target"))
    header_row.insertCell().appendChild(document.createTextNode("Diffs"))


    table_body = shift_count_table.createTBody()

    for (const shift in shifts) {
        let row = table_body.insertRow();
        row.insertCell().appendChild(document.createTextNode(shift))
        row.insertCell().appendChild(document.createTextNode(shifts[shift]))
        row.insertCell().appendChild(document.createTextNode(shift_targets[shift].toPrecision(2)))
        row.insertCell().appendChild(document.createTextNode(shift_diffs[shift].toPrecision(2)))
    }

    dlg.get(0).appendChild(shift_count_table)
    dlg.dialog()



}

$("#export-div").append($("#main-table").clone().attr("id", "gen-table").addClass("transposed"))

$("#gen-table").each(function () {
    var $this = $(this);
    var newrows = [];
    //$this.find("th.site-title").parent().remove();
    $this.find("tr").each(function (rowToColIndex) {
        $(this).find("td, th").each(function (colToRowIndex) {
            if (newrows[colToRowIndex] === undefined) {
                newrows[colToRowIndex] = $("<tr></tr>");
            }
            while (newrows[colToRowIndex].find("td, th").length < rowToColIndex) {
                newrows[colToRowIndex].append($("<td></td>"));
            }
            newrows[colToRowIndex].append($(this));
        });
    });
    $this.find("tr").remove();
    $.each(newrows, function () {
        $this.append(this);
    });

    $this.find("td.rota-day").each((n, el) => {
        $(el).text(el.dataset.shift)
    });
});

// ICS Export functionality
let customShiftTimes = {}; // Will store user-defined times

function getShiftTimes() {
    // Merge default with custom
    const defaultTimes = {
        'night_weekday': { start: '20:00', end: '08:15', nextDay: true },
        'night_weekend': { start: '20:00', end: '08:15', nextDay: true },
        'exeter_twilight': { start: '14:00', end: '02:30', nextDay: true },
        'truro_twilight': { start: '14:00', end: '02:30', nextDay: true },
        'torbay_twilight': { start: '14:00', end: '02:30', nextDay: true },
        'plymouth_twilight': { start: '14:00', end: '02:30', nextDay: true },
        'weekend_exeter': { start: '08:00', end: '20:30', nextDay: false },
        'weekend_truro': { start: '08:00', end: '20:30', nextDay: false },
        'weekend_torbay': { start: '08:00', end: '20:30', nextDay: false },
        'weekend_plymouth1': { start: '08:00', end: '16:00', nextDay: false },
        'weekend_plymouth2': { start: '16:00', end: '00:00', nextDay: false },
        'plymouth_bank_holidays': { start: '08:00', end: '16:00', nextDay: false },
    };
    return { ...defaultTimes, ...customShiftTimes };
}

function generateICS(shiftType, shiftData) {
    let icsContent = `BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Rota Generator//EN
`;

    const shiftTimes = getShiftTimes();
    const time = shiftTimes[shiftType] || { start: '09:00', end: '17:00', nextDay: false };

    shiftData.forEach(entry => {
        const date = entry.date;
        const workerName = entry.worker;
        
        const startDate = new Date(date + 'T' + time.start + ':00');
        let endDate = new Date(date + 'T' + time.end + ':00');
        if (time.nextDay) {
            endDate.setDate(endDate.getDate() + 1);
        }

        const formatDate = (d) => d.toISOString().replace(/[-:]/g, '').split('.')[0] + 'Z';

        const shiftTitle = shiftType.replace(/_/g, ' ').toUpperCase();
        const summary = workerName ? `${shiftTitle} - ${workerName}` : shiftTitle;
        const description = workerName ? 
            `Shift: ${shiftType}\nWorker: ${workerName}` : 
            `Shift: ${shiftType}`;

        icsContent += `BEGIN:VEVENT
UID:${workerName ? workerName + '-' : ''}${shiftType}-${date}@rota
DTSTAMP:${formatDate(new Date())}
DTSTART:${formatDate(startDate)}
DTEND:${formatDate(endDate)}
SUMMARY:${summary}
DESCRIPTION:${description}
END:VEVENT
`;
    });

    icsContent += 'END:VCALENDAR';
    return icsContent;
}

function downloadICS(filename, content) {
    const blob = new Blob([content], { type: 'text/calendar;charset=utf-8' });
    const link = document.createElement('a');
    link.href = URL.createObjectURL(blob);
    link.download = filename;
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
}

// Collect shift dates and worker assignments
const shiftDates = {};
const workerShifts = {};

$('#main-table tr.worker-row').each(function() {
    const workerName = $(this).find('td.worker').attr('data-worker');
    if (workerName) {
        workerShifts[workerName] = {};
        
        $(this).find('td.rota-day').each(function() {
            const shift = $(this).attr('data-shift');
            const date = $(this).attr('data-date');
            if (shift && shift !== '' && date) {
                const shifts = shift.split(',').map(s => s.trim()).filter(s => s);
                shifts.forEach(s => {
                    // Collect by shift type with worker info
                    if (!shiftDates[s]) {
                        shiftDates[s] = [];
                    }
                    // Check if we already have this date for this shift type
                    const existingEntry = shiftDates[s].find(entry => entry.date === date);
                    if (!existingEntry) {
                        shiftDates[s].push({ date: date, worker: workerName });
                    }
                    
                    // Collect by worker
                    if (!workerShifts[workerName][s]) {
                        workerShifts[workerName][s] = [];
                    }
                    if (!workerShifts[workerName][s].includes(date)) {
                        workerShifts[workerName][s].push(date);
                    }
                });
            }
        });
    }
});

// Add ICS export buttons
const icsButtonsDiv = $('<div id="ics-export-buttons" style="margin-top: 20px;"><h3>Export ICS Files</h3></div>');
const setTimesButton = $(`<button id="set-shift-times" style="margin: 5px;">Set Shift Times</button>`);
icsButtonsDiv.append(setTimesButton);

// Shift type exports (with worker info)
const shiftExportsDiv = $('<div style="margin-bottom: 20px;"><h4>Export by Shift Type</h4></div>');
Object.keys(shiftDates).sort().forEach(shiftType => {
    const button = $(`<button style="margin: 5px;">Download ${shiftType.replace(/_/g, ' ')} ICS</button>`);
    button.on('click', () => {
        const ics = generateICS(shiftType, shiftDates[shiftType]);
        downloadICS(`${shiftType}.ics`, ics);
    });
    shiftExportsDiv.append(button);
});
icsButtonsDiv.append(shiftExportsDiv);

// Worker exports
const workerExportsDiv = $('<div style="margin-bottom: 20px;"><h4>Export by Worker</h4></div>');
Object.keys(workerShifts).sort().forEach(workerName => {
    const workerShiftTypes = Object.keys(workerShifts[workerName]);
    if (workerShiftTypes.length > 0) {
        const button = $(`<button style="margin: 5px;">Download ${workerName} ICS</button>`);
        button.on('click', () => {
            showWorkerShiftSelectionModal(workerName, workerShifts[workerName]);
        });
        workerExportsDiv.append(button);
    }
});
icsButtonsDiv.append(workerExportsDiv);

$('#export-div').append(icsButtonsDiv);

// Function to show worker shift selection modal
function showWorkerShiftSelectionModal(workerName, workerShiftData) {
    const checkboxesDiv = $('#worker-shift-checkboxes');
    checkboxesDiv.empty();
    
    $('#worker-shift-modal-title').text(`Select Shifts for ${workerName}`);
    
    // Create checkboxes for each shift type
    Object.keys(workerShiftData).sort().forEach(shiftType => {
        const dates = workerShiftData[shiftType];
        const checkboxId = `shift-${shiftType}`;
        const checkbox = $(`
            <div style="margin: 8px 0;">
                <input type="checkbox" id="${checkboxId}" checked>
                <label for="${checkboxId}" style="margin-left: 8px;">
                    ${shiftType.replace(/_/g, ' ').toUpperCase()} (${dates.length} shift${dates.length !== 1 ? 's' : ''})
                </label>
            </div>
        `);
        checkboxesDiv.append(checkbox);
    });
    
    // Store worker data for export
    $('#worker-shift-export').data('workerName', workerName);
    $('#worker-shift-export').data('workerShiftData', workerShiftData);
    
    // Show modal
    workerShiftModal.show();
}

// Modal for worker shift selection
const workerShiftModal = $(`
<div id="worker-shift-modal" style="display:none; position:fixed; top:50%; left:50%; transform:translate(-50%,-50%); z-index:10000; background:#fff; border:2px solid #888; border-radius:8px; box-shadow:0 4px 24px #0002; padding:24px; min-width:400px; max-height:80vh; overflow-y:auto;">
    <h3 style="margin-top:0;" id="worker-shift-modal-title">Select Shifts for Export</h3>
    <div id="worker-shift-checkboxes" style="margin: 16px 0;"></div>
    <div style="text-align:right; margin-top:16px;">
        <button id="worker-shift-cancel" style="margin-right:8px;">Cancel</button>
        <button id="worker-shift-export">Export Selected</button>
    </div>
</div>
`);
$('body').append(workerShiftModal);

// Modal for setting shift times
const shiftTimesModal = $(`
<div id="shift-times-modal" style="display:none; position:fixed; top:50%; left:50%; transform:translate(-50%,-50%); z-index:10000; background:#fff; border:2px solid #888; border-radius:8px; box-shadow:0 4px 24px #0002; padding:24px; min-width:400px; max-height:80vh; overflow-y:auto;">
    <h3 style="margin-top:0;">Set Shift Times</h3>
    <div id="shift-times-controls"></div>
    <div style="text-align:right; margin-top:16px;">
        <button id="save-shift-times">Save</button>
        <button id="close-shift-times">Close</button>
    </div>
</div>
`);
$("body").append(shiftTimesModal);

$('#set-shift-times').on('click', function() {
    $('#shift-times-modal').show();
    populateShiftTimesModal();
});

$('#close-shift-times').on('click', function() {
    $('#shift-times-modal').hide();
});

$('#save-shift-times').on('click', function() {
    saveShiftTimes();
    $('#shift-times-modal').hide();
});

// Worker shift modal event handlers
$('#worker-shift-cancel').on('click', function() {
    workerShiftModal.hide();
});

$('#worker-shift-export').on('click', function() {
    const workerName = $(this).data('workerName');
    const workerShiftData = $(this).data('workerShiftData');
    
    // Get selected shift types
    const selectedShifts = [];
    $('#worker-shift-checkboxes input[type="checkbox"]:checked').each(function() {
        const shiftType = $(this).attr('id').replace('shift-', '');
        selectedShifts.push(shiftType);
    });
    
    if (selectedShifts.length === 0) {
        alert('Please select at least one shift type to export.');
        return;
    }
    
    // Generate ICS for selected shifts
    let icsContent = `BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Rota Generator//EN
`;
    
    selectedShifts.forEach(shiftType => {
        const dates = workerShiftData[shiftType];
        const shiftTimes = getShiftTimes();
        const time = shiftTimes[shiftType] || { start: '09:00', end: '17:00', nextDay: false };
        
        dates.forEach(date => {
            const startDate = new Date(date + 'T' + time.start + ':00');
            let endDate = new Date(date + 'T' + time.end + ':00');
            if (time.nextDay) {
                endDate.setDate(endDate.getDate() + 1);
            }
            
            const formatDate = (d) => d.toISOString().replace(/[-:]/g, '').split('.')[0] + 'Z';
            
            const shiftTitle = shiftType.replace(/_/g, ' ').toUpperCase();
            
            icsContent += `BEGIN:VEVENT
UID:${workerName}-${shiftType}-${date}@rota
DTSTAMP:${formatDate(new Date())}
DTSTART:${formatDate(startDate)}
DTEND:${formatDate(endDate)}
SUMMARY:${shiftTitle} - ${workerName}
DESCRIPTION:Shift: ${shiftType}\nWorker: ${workerName}
END:VEVENT
`;
        });
    });
    
    icsContent += 'END:VCALENDAR';
    downloadICS(`${workerName.replace(/[^a-zA-Z0-9]/g, '_')}.ics`, icsContent);
    
    workerShiftModal.hide();
});

function populateShiftTimesModal() {
    const controls = $('#shift-times-controls');
    controls.empty();
    const shiftTimes = getShiftTimes();
    Object.keys(shiftDates).sort().forEach(shiftType => {
        const time = shiftTimes[shiftType] || { start: '09:00', end: '17:00', nextDay: false };
        const div = $(`
            <div style="margin: 10px 0; padding: 10px; border: 1px solid #ccc; border-radius: 4px;">
                <label><strong>${shiftType.replace(/_/g, ' ')}</strong></label><br>
                <label>Start: <input type="time" class="shift-start" data-shift="${shiftType}" value="${time.start}"></label>
                <label>End: <input type="time" class="shift-end" data-shift="${shiftType}" value="${time.end}"></label>
                <label><input type="checkbox" class="shift-nextday" data-shift="${shiftType}" ${time.nextDay ? 'checked' : ''}> Ends next day</label>
            </div>
        `);
        controls.append(div);
    });
}

function saveShiftTimes() {
    customShiftTimes = {};
    $('#shift-times-controls .shift-start').each(function() {
        const shift = $(this).data('shift');
        const start = $(this).val();
        const end = $(`input.shift-end[data-shift="${shift}"]`).val();
        const nextDay = $(`input.shift-nextday[data-shift="${shift}"]`).is(':checked');
        customShiftTimes[shift] = { start, end, nextDay };
    });
}

function hsv2rgb(h, s, v) {
    // adapted from http://schinckel.net/2012/01/10/hsv-to-rgb-in-javascript/
    var rgb, i, data = [];
    if (s === 0) {
        rgb = [v, v, v];
    } else {
        h = h / 60;
        i = Math.floor(h);
        data = [v * (1 - s), v * (1 - s * (h - i)), v * (1 - s * (1 - (h - i)))];
        switch (i) {
            case 0:
                rgb = [v, data[2], data[0]];
                break;
            case 1:
                rgb = [data[1], v, data[0]];
                break;
            case 2:
                rgb = [data[0], v, data[2]];
                break;
            case 3:
                rgb = [data[0], data[1], v];
                break;
            case 4:
                rgb = [data[2], data[0], v];
                break;
            default:
                rgb = [v, data[0], data[1]];
                break;
        }
    }
    return '#' + rgb.map(function (x) {
        return ("0" + Math.round(x * 255).toString(16)).slice(-2);
    }).join('');
};