/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/
import * as strings from '../../../base/common/strings.js';
import { IndentAction } from './languageConfiguration.js';
import { createScopedLineTokens } from './supports.js';
import { getScopedLineTokens } from './languageConfigurationRegistry.js';
/**
 * Get nearest preceding line which doesn't match unIndentPattern or contains all whitespace.
 * Result:
 * -1: run into the boundary of embedded languages
 * 0: every line above are invalid
 * else: nearest preceding line of the same language
 */
function getPrecedingValidLine(model, lineNumber, indentRulesSupport) {
    const languageId = model.tokenization.getLanguageIdAtPosition(lineNumber, 0);
    if (lineNumber > 1) {
        let lastLineNumber;
        let resultLineNumber = -1;
        for (lastLineNumber = lineNumber - 1; lastLineNumber >= 1; lastLineNumber--) {
            if (model.tokenization.getLanguageIdAtPosition(lastLineNumber, 0) !== languageId) {
                return resultLineNumber;
            }
            const text = model.getLineContent(lastLineNumber);
            if (indentRulesSupport.shouldIgnore(text) || /^\s+$/.test(text) || text === '') {
                resultLineNumber = lastLineNumber;
                continue;
            }
            return lastLineNumber;
        }
    }
    return -1;
}
/**
 * Get inherited indentation from above lines.
 * 1. Find the nearest preceding line which doesn't match unIndentedLinePattern.
 * 2. If this line matches indentNextLinePattern or increaseIndentPattern, it means that the indent level of `lineNumber` should be 1 greater than this line.
 * 3. If this line doesn't match any indent rules
 *   a. check whether the line above it matches indentNextLinePattern
 *   b. If not, the indent level of this line is the result
 *   c. If so, it means the indent of this line is *temporary*, go upward utill we find a line whose indent is not temporary (the same workflow a -> b -> c).
 * 4. Otherwise, we fail to get an inherited indent from aboves. Return null and we should not touch the indent of `lineNumber`
 *
 * This function only return the inherited indent based on above lines, it doesn't check whether current line should decrease or not.
 */
export function getInheritIndentForLine(autoIndent, model, lineNumber, honorIntentialIndent = true, languageConfigurationService) {
    if (autoIndent < 4 /* EditorAutoIndentStrategy.Full */) {
        return null;
    }
    const indentRulesSupport = languageConfigurationService.getLanguageConfiguration(model.tokenization.getLanguageId()).indentRulesSupport;
    if (!indentRulesSupport) {
        return null;
    }
    if (lineNumber <= 1) {
        return {
            indentation: '',
            action: null
        };
    }
    const precedingUnIgnoredLine = getPrecedingValidLine(model, lineNumber, indentRulesSupport);
    if (precedingUnIgnoredLine < 0) {
        return null;
    }
    else if (precedingUnIgnoredLine < 1) {
        return {
            indentation: '',
            action: null
        };
    }
    const precedingUnIgnoredLineContent = model.getLineContent(precedingUnIgnoredLine);
    if (indentRulesSupport.shouldIncrease(precedingUnIgnoredLineContent) || indentRulesSupport.shouldIndentNextLine(precedingUnIgnoredLineContent)) {
        return {
            indentation: strings.getLeadingWhitespace(precedingUnIgnoredLineContent),
            action: IndentAction.Indent,
            line: precedingUnIgnoredLine
        };
    }
    else if (indentRulesSupport.shouldDecrease(precedingUnIgnoredLineContent)) {
        return {
            indentation: strings.getLeadingWhitespace(precedingUnIgnoredLineContent),
            action: null,
            line: precedingUnIgnoredLine
        };
    }
    else {
        // precedingUnIgnoredLine can not be ignored.
        // it doesn't increase indent of following lines
        // it doesn't increase just next line
        // so current line is not affect by precedingUnIgnoredLine
        // and then we should get a correct inheritted indentation from above lines
        if (precedingUnIgnoredLine === 1) {
            return {
                indentation: strings.getLeadingWhitespace(model.getLineContent(precedingUnIgnoredLine)),
                action: null,
                line: precedingUnIgnoredLine
            };
        }
        const previousLine = precedingUnIgnoredLine - 1;
        const previousLineIndentMetadata = indentRulesSupport.getIndentMetadata(model.getLineContent(previousLine));
        if (!(previousLineIndentMetadata & (1 /* IndentConsts.INCREASE_MASK */ | 2 /* IndentConsts.DECREASE_MASK */)) &&
            (previousLineIndentMetadata & 4 /* IndentConsts.INDENT_NEXTLINE_MASK */)) {
            let stopLine = 0;
            for (let i = previousLine - 1; i > 0; i--) {
                if (indentRulesSupport.shouldIndentNextLine(model.getLineContent(i))) {
                    continue;
                }
                stopLine = i;
                break;
            }
            return {
                indentation: strings.getLeadingWhitespace(model.getLineContent(stopLine + 1)),
                action: null,
                line: stopLine + 1
            };
        }
        if (honorIntentialIndent) {
            return {
                indentation: strings.getLeadingWhitespace(model.getLineContent(precedingUnIgnoredLine)),
                action: null,
                line: precedingUnIgnoredLine
            };
        }
        else {
            // search from precedingUnIgnoredLine until we find one whose indent is not temporary
            for (let i = precedingUnIgnoredLine; i > 0; i--) {
                const lineContent = model.getLineContent(i);
                if (indentRulesSupport.shouldIncrease(lineContent)) {
                    return {
                        indentation: strings.getLeadingWhitespace(lineContent),
                        action: IndentAction.Indent,
                        line: i
                    };
                }
                else if (indentRulesSupport.shouldIndentNextLine(lineContent)) {
                    let stopLine = 0;
                    for (let j = i - 1; j > 0; j--) {
                        if (indentRulesSupport.shouldIndentNextLine(model.getLineContent(i))) {
                            continue;
                        }
                        stopLine = j;
                        break;
                    }
                    return {
                        indentation: strings.getLeadingWhitespace(model.getLineContent(stopLine + 1)),
                        action: null,
                        line: stopLine + 1
                    };
                }
                else if (indentRulesSupport.shouldDecrease(lineContent)) {
                    return {
                        indentation: strings.getLeadingWhitespace(lineContent),
                        action: null,
                        line: i
                    };
                }
            }
            return {
                indentation: strings.getLeadingWhitespace(model.getLineContent(1)),
                action: null,
                line: 1
            };
        }
    }
}
export function getGoodIndentForLine(autoIndent, virtualModel, languageId, lineNumber, indentConverter, languageConfigurationService) {
    if (autoIndent < 4 /* EditorAutoIndentStrategy.Full */) {
        return null;
    }
    const richEditSupport = languageConfigurationService.getLanguageConfiguration(languageId);
    if (!richEditSupport) {
        return null;
    }
    const indentRulesSupport = languageConfigurationService.getLanguageConfiguration(languageId).indentRulesSupport;
    if (!indentRulesSupport) {
        return null;
    }
    const indent = getInheritIndentForLine(autoIndent, virtualModel, lineNumber, undefined, languageConfigurationService);
    const lineContent = virtualModel.getLineContent(lineNumber);
    if (indent) {
        const inheritLine = indent.line;
        if (inheritLine !== undefined) {
            // Apply enter action as long as there are only whitespace lines between inherited line and this line.
            let shouldApplyEnterRules = true;
            for (let inBetweenLine = inheritLine; inBetweenLine < lineNumber - 1; inBetweenLine++) {
                if (!/^\s*$/.test(virtualModel.getLineContent(inBetweenLine))) {
                    shouldApplyEnterRules = false;
                    break;
                }
            }
            if (shouldApplyEnterRules) {
                const enterResult = richEditSupport.onEnter(autoIndent, '', virtualModel.getLineContent(inheritLine), '');
                if (enterResult) {
                    let indentation = strings.getLeadingWhitespace(virtualModel.getLineContent(inheritLine));
                    if (enterResult.removeText) {
                        indentation = indentation.substring(0, indentation.length - enterResult.removeText);
                    }
                    if ((enterResult.indentAction === IndentAction.Indent) ||
                        (enterResult.indentAction === IndentAction.IndentOutdent)) {
                        indentation = indentConverter.shiftIndent(indentation);
                    }
                    else if (enterResult.indentAction === IndentAction.Outdent) {
                        indentation = indentConverter.unshiftIndent(indentation);
                    }
                    if (indentRulesSupport.shouldDecrease(lineContent)) {
                        indentation = indentConverter.unshiftIndent(indentation);
                    }
                    if (enterResult.appendText) {
                        indentation += enterResult.appendText;
                    }
                    return strings.getLeadingWhitespace(indentation);
                }
            }
        }
        if (indentRulesSupport.shouldDecrease(lineContent)) {
            if (indent.action === IndentAction.Indent) {
                return indent.indentation;
            }
            else {
                return indentConverter.unshiftIndent(indent.indentation);
            }
        }
        else {
            if (indent.action === IndentAction.Indent) {
                return indentConverter.shiftIndent(indent.indentation);
            }
            else {
                return indent.indentation;
            }
        }
    }
    return null;
}
export function getIndentForEnter(autoIndent, model, range, indentConverter, languageConfigurationService) {
    if (autoIndent < 4 /* EditorAutoIndentStrategy.Full */) {
        return null;
    }
    model.tokenization.forceTokenization(range.startLineNumber);
    const lineTokens = model.tokenization.getLineTokens(range.startLineNumber);
    const scopedLineTokens = createScopedLineTokens(lineTokens, range.startColumn - 1);
    const scopedLineText = scopedLineTokens.getLineContent();
    let embeddedLanguage = false;
    let beforeEnterText;
    if (scopedLineTokens.firstCharOffset > 0 && lineTokens.getLanguageId(0) !== scopedLineTokens.languageId) {
        // we are in the embeded language content
        embeddedLanguage = true; // if embeddedLanguage is true, then we don't touch the indentation of current line
        beforeEnterText = scopedLineText.substr(0, range.startColumn - 1 - scopedLineTokens.firstCharOffset);
    }
    else {
        beforeEnterText = lineTokens.getLineContent().substring(0, range.startColumn - 1);
    }
    let afterEnterText;
    if (range.isEmpty()) {
        afterEnterText = scopedLineText.substr(range.startColumn - 1 - scopedLineTokens.firstCharOffset);
    }
    else {
        const endScopedLineTokens = getScopedLineTokens(model, range.endLineNumber, range.endColumn);
        afterEnterText = endScopedLineTokens.getLineContent().substr(range.endColumn - 1 - scopedLineTokens.firstCharOffset);
    }
    const indentRulesSupport = languageConfigurationService.getLanguageConfiguration(scopedLineTokens.languageId).indentRulesSupport;
    if (!indentRulesSupport) {
        return null;
    }
    const beforeEnterResult = beforeEnterText;
    const beforeEnterIndent = strings.getLeadingWhitespace(beforeEnterText);
    const virtualModel = {
        tokenization: {
            getLineTokens: (lineNumber) => {
                return model.tokenization.getLineTokens(lineNumber);
            },
            getLanguageId: () => {
                return model.getLanguageId();
            },
            getLanguageIdAtPosition: (lineNumber, column) => {
                return model.getLanguageIdAtPosition(lineNumber, column);
            },
        },
        getLineContent: (lineNumber) => {
            if (lineNumber === range.startLineNumber) {
                return beforeEnterResult;
            }
            else {
                return model.getLineContent(lineNumber);
            }
        }
    };
    const currentLineIndent = strings.getLeadingWhitespace(lineTokens.getLineContent());
    const afterEnterAction = getInheritIndentForLine(autoIndent, virtualModel, range.startLineNumber + 1, undefined, languageConfigurationService);
    if (!afterEnterAction) {
        const beforeEnter = embeddedLanguage ? currentLineIndent : beforeEnterIndent;
        return {
            beforeEnter: beforeEnter,
            afterEnter: beforeEnter
        };
    }
    let afterEnterIndent = embeddedLanguage ? currentLineIndent : afterEnterAction.indentation;
    if (afterEnterAction.action === IndentAction.Indent) {
        afterEnterIndent = indentConverter.shiftIndent(afterEnterIndent);
    }
    if (indentRulesSupport.shouldDecrease(afterEnterText)) {
        afterEnterIndent = indentConverter.unshiftIndent(afterEnterIndent);
    }
    return {
        beforeEnter: embeddedLanguage ? currentLineIndent : beforeEnterIndent,
        afterEnter: afterEnterIndent
    };
}
/**
 * We should always allow intentional indentation. It means, if users change the indentation of `lineNumber` and the content of
 * this line doesn't match decreaseIndentPattern, we should not adjust the indentation.
 */
export function getIndentActionForType(autoIndent, model, range, ch, indentConverter, languageConfigurationService) {
    if (autoIndent < 4 /* EditorAutoIndentStrategy.Full */) {
        return null;
    }
    const scopedLineTokens = getScopedLineTokens(model, range.startLineNumber, range.startColumn);
    if (scopedLineTokens.firstCharOffset) {
        // this line has mixed languages and indentation rules will not work
        return null;
    }
    const indentRulesSupport = languageConfigurationService.getLanguageConfiguration(scopedLineTokens.languageId).indentRulesSupport;
    if (!indentRulesSupport) {
        return null;
    }
    const scopedLineText = scopedLineTokens.getLineContent();
    const beforeTypeText = scopedLineText.substr(0, range.startColumn - 1 - scopedLineTokens.firstCharOffset);
    // selection support
    let afterTypeText;
    if (range.isEmpty()) {
        afterTypeText = scopedLineText.substr(range.startColumn - 1 - scopedLineTokens.firstCharOffset);
    }
    else {
        const endScopedLineTokens = getScopedLineTokens(model, range.endLineNumber, range.endColumn);
        afterTypeText = endScopedLineTokens.getLineContent().substr(range.endColumn - 1 - scopedLineTokens.firstCharOffset);
    }
    // If previous content already matches decreaseIndentPattern, it means indentation of this line should already be adjusted
    // Users might change the indentation by purpose and we should honor that instead of readjusting.
    if (!indentRulesSupport.shouldDecrease(beforeTypeText + afterTypeText) && indentRulesSupport.shouldDecrease(beforeTypeText + ch + afterTypeText)) {
        // after typing `ch`, the content matches decreaseIndentPattern, we should adjust the indent to a good manner.
        // 1. Get inherited indent action
        const r = getInheritIndentForLine(autoIndent, model, range.startLineNumber, false, languageConfigurationService);
        if (!r) {
            return null;
        }
        let indentation = r.indentation;
        if (r.action !== IndentAction.Indent) {
            indentation = indentConverter.unshiftIndent(indentation);
        }
        return indentation;
    }
    return null;
}
export function getIndentMetadata(model, lineNumber, languageConfigurationService) {
    const indentRulesSupport = languageConfigurationService.getLanguageConfiguration(model.getLanguageId()).indentRulesSupport;
    if (!indentRulesSupport) {
        return null;
    }
    if (lineNumber < 1 || lineNumber > model.getLineCount()) {
        return null;
    }
    return indentRulesSupport.getIndentMetadata(model.getLineContent(lineNumber));
}
